Boosted_Dreams

I have a lq9 and truck accessories with ls6 intake. Installed a vortech v3 and kit came with a manual tensioner. To clear the throttle body I have to adjust the tensioner low enough. Trying to find a spring loaded tensioner that would work. The short arm truck tensioner does not help.

Rich-L79

Stick with the manual tensioner. That long stretch of belt can get to flapping and with a spring loaded tensioner the belt could rub on the thermostat housing or skip off the pulley altogether. Throwing the belt off and shredding it on my LS2 once was enough for me before I put on a manual tensioner and never had belt problems again. Oh, and always carry a spare belt and a wrench or two enough to change the belt on the side of the road if you have to.

Also, your pictures are a little confusing, the belt routing is different in each. Either way, there are some super long stretches of belt there, lots of room for belts to wiggle and flap and come off a pulley.

Brutus

Went from a manual tensioner to auto and cured my belt slip issue albiet different set up.

Boosted_Dreams

Sorry for the confusion. I tried two seprate ways to run the belt. The way vortech wants and then giving the stock tensioner a try. The reason I am in need of this. I have boost 10lbs up to about 4k rpm. Especially if I roll into the gas. If I stomp the gas the boost falls off sooner. I will hold around 5lbs at 6k rpm. I originally thought it was a lack of blower. So I went to a smaller pulley. After hitting the dyno, I was told that was way to small to get traction on a 6 rib and try a larger one, he suggested 3.4 might be a good one, if not go back to the stock 3.6. Now with the griptec 3.4 and still having a lack of boost at the top, I'm lost.

forcd ind

iTrader: (7)

Usually on a serpentine belt a spring loaded idler works best, that's a lot of belt though. I have added fixed idlers to help belt wrap, but you have good wrap on the SC. You could try a shorter belt, maybe I missed where it hits the TB. Did Vortec have any ideas, at one time I was going to try that setup.

dlandsvZ28

No matter what you decide to do with respect to the belt tensioner, I would switch the belt to the Gates RPM product line in lieu of the Gates ''Green' belt.

Gates claims the RPM belt doesn't stretch like the Green belt. You don't have to run it as tight either as the Green belt as claimed in the link below.

https://www.svtperformance.com/threa...lower.1140578/

customblackbird

iTrader: (2)

Are you sure it’s belt slip? Did you find any rubber shavings or hear it?

another thing to consider is the supercharger intake (filter side) a restriction here kills boost as you start to spin it up where the restriction takes place. Also a restriction on the outlet if your running a FMIC or A2W setup can also kill boost and the obvious boost leak.

so good high flow filter and limited tube/bends on the intake side. Make sure the inter cooling side flows enough and there are no boost leaks.

when I had belt slip on a centri it was a small 3” pulley (torque storm) and I hade that gates green belt cranked down. I could hear the squeal when it slipped but only on heavy throttle. I could also see some belt dust. I played with intske tube length (3.5” tube and a good AEM dry flow filter) and found that more bends to get fresh air affected boost output and same does for smaller intercoolers to help gain more airflow restricted boost.

I always heard auto tensioners are not the best for superchargers and manual was better.

nuckifuts

iTrader: (7)

I have not data logged my setup but I believe I have belt slip as well.

What Crank pulley are you using to get 10 PSI?

I have an LQ4 with the C5 Swap kit. V3 head unit. With a 7.8" crank and 3.33" blower pulley I can only get 7-8 PSI at redline according to the person who tuned it. That is with a 10 rib RPM and Green belt.

I have tried a billet manual tensioner and had the pullies etched and no difference except for belt dust. I was warned about that before I installed it, should have listened.

I tried to add another idler below the blower but it will put the belt into the thermostat housing.

Boosted_Dreams

I believe I might have found a solution. After many hours of searching I found a company that sells a waterpump mount belt tensioner bracket.https://atomicfabandperformance.com/...ioner-bracket/ then I used a 6.7 cummins belt tensioner. Part #38285 gates. That tensioner rotation is counterclockwise with a smooth idler pulley. I Currently am using a 120 1/8 belt but I might go to a 120 7/8 belt on next one. I am going to put it all back together and see how it goes.

Franco Sj

Hey man, I found you forum after hours of searching for something to help the belt slip also. I saw that you did this. Did this help at all? Please let me know. I would appreciate it. Thank you

Boosted_Dreams

Night and day difference. Boost fell off after 4000rpm and was pretty much just a noise maker. Now I see 10lbs when I shift at 6k rpm. Also the intercooler works great too. I noticed better cooling with just water compared to diluted coolant.

Franco Sj

Great. Than you. And all you did was get that bracket and tensioner? And took off one of the idler pullets along with the manual tensioner on the bracket?

Boosted_Dreams

I kept the manual tensioner to pull the belt down to clear the ls6 throttle body and removed the idler below that for the spring loaded one. So there is a manual and spring loaded tensioner on my setup.

Boosted_luxurysport

So based on the images that boosted_dreams posted I order both the bracket and tensioner and have issues getting the bracket to lineup to the other bracket on the suoercharger.. I need help

BoostedBubble

Did you ever get the issue resolved??

Boosted_luxurysport

no i did not

Novarox87

Hey guys just wanted to share my experience with installing the spring loaded tensioner and bracket, boosted dreams used. I also used the same bracket and tensioner pulley he posted on a previous post. The only thing I had to do was add washers to space the bracket away from the Vortech supercharger's bracket. (Later I will add proper spacers). Even though the tensioner does get pushed out further away, it is still is in line with the belt. This definitely made a huge difference, I took my car to get Dyno tuned before the upgrades and I was only getting 4.5 pounds of boost, after 4k rpm, boost started falling off. I have not taken it back to the Dyno yet but my boost gauge now reads between 9-10 pounds, it is a different animal now. I will be taking it back to the Dyno hopefully within a month. I'm using a Griptech 3.25" pulley the belt I used is 117". I recommend anybody having belt slip issues with this set up to do these upgrades ASAP!

dawgs74

so what exactly did you have to get for this to work….just the bracket and tensioner from the link the OP posted….and then put a smooth idler on instead of the 6groove….im just curious cause i have the same setup on my swapped c/10, its just a cruiser i dont race it but i already have a 2.87” pulley and i think im having a belt slip issue as well…..i cant seem too see more than 5lbs psi so something is happening…..did u get the tensioner from that website too? (Link)…or did you source it from a cheaper vendor…..im looking at a $250ish fix correct???

dawgs74

Novarox87

All that was needed was the bracket from the link above and I got the smooth pulley tensioner off Amazon, Gates part number 38285, you'll also need a new belt, in my case I needed a 1" longer belt. Washers were needed to push the new bracket forward so that the tensioner pulleys bolt has clearance from the vortech supercharger bracket. I would definitely do this upgrade to help with belt slip. But I have also read that to small of a pulley such as yours can have belt slip even with a tensioner pulley set up. Do the upgrades, if you still have slip issues I would put the original 3.6 back on and see what it does.